On the Origin of Glycocoll in the Animal Body. 103 
limits runs parallel to the amount of benzoic acid fed. In period 
VI., it reached its maximum. 384 per cent, of the total N was 
eliminated as glycocoll N in the hippuric acid. 
Where do these enormous quantities of glycocoll originate? 
It might be argued that the source of the glycocoll found in the 
system lies in the different vegetable foods which are known to 
contain rather large quantities of free amino-bodies. But after 
giving 8 grams of sodium benzoate to a calf two weeks old which 
had had no other form of food but milk, the protein of which 
contains no glycocoll, it was found that it was able to form and 
eliminate hippuric acid glycocoll as readily as the adult goat. 
Ingestion of glycolic or glyoxylic acid with very large quan- 
tities of sodium benzoate in rabbits, does not increase the quantity 
of glycocoll formed as indicated by the amount of hippuric acid 
eliminated. This might have been possible from their chemical 
relationship to glycocoll. (A detailed account of these experi- 
ments will be given in the final report.) 
On careful consideration of the nitrogen metabolism in animals 
during the benzoate period, a possible explanation of the origin 
of glycocoll suggests itself. The goat during the three days of 
the foreperiod, excreted an average of 5.6 grams of N. Excepting 
the first day, which may be due to a sudden change in the quantity 
of food, there is a marked rise in the protein metabolism through- 
out the course of the benzoate period. This was observed in all 
the experiments and in all the varieties of animals that have been 
experimented upon. Furthermore, the increase in the protein 
destruction, i. e., that increase in the N elimination above the 
normal, or above a previous day of a smaller benzoate dose, is 
always two to three times greater than the amount of nitrogen 
that has been eliminated as glycocoll in the hippuric acid molecule. 
In Table II., the results of experiments on two rabbits are 
recorded. These show that the amount of urea N plus ammonia 
N during the benzoate period does not differ from normal days, 
and also that the extra N catabolized is much greater than the 
amount of N that was eliminated in the form of hippuric acid. 
All these facts suggest the possibility that the glycocoll ex- 
creted as hippuric acid does not come from the fraction of protein 
that would have been metabolized had no benzoate been given, 
